Treatment compositions for fresh concrete or mortar surfaces which offer improved adhesion capacity and water retention power

ABSTRACT

The invention relates to compositions intended to be applied to the surfaces of freshly poured mortars and/or concretes, before the beginning of the setting, in order simultaneously to prevent the evaporation of the water present in said mortars and/or concretes, which is necessary for their setting and then for their hardening, and in order to create, on said treated surfaces, high adhesiveness for the finishing materials intended to cover them, these compositions being provided in the form of aqueous emulsions comprising at least one paraffin wax (a), alone or in combination with at least one hydrocarbon compound (b) and/or with at least one other hydrocarbon compound (c) different from the hydrocarbon compound (b), and also comprising at least one latex (d) formed of a colloidal aqueous emulsion of at least one polymer, and at least one pulverulent inorganic or organic filler (e).

FIELD OF THE INVENTION

The invention relates to aqueous compositions for the treatment of thesurfaces of freshly placed or freshly demolded mortars and/or concreteswhich provide the water retention necessary for their setting and theirhardening and which bestow, on said treated surfaces, high adhesivenessfor the finishing materials intended to cover them.

The invention relates more particularly to curing compositions for thesurfaces of freshly placed or freshly demolded mortars and/or concretesin order to prevent the evaporation of a portion of the water involvedin their preparation, this water being necessary for their setting andtheir hardening, and in order to give the surfaces thus treated highadhesiveness for the finishing materials intended to cover them, whichcompositions comprise, in an aqueous emulsion, at least one paraffinwax, alone or in combination with another hydrocarbon compound in thesolid and/or liquid state at ambient temperature, such as, for example,natural or synthetic hydrocarbon waxes and/or oils, at least one latexand at least one pulverulent filler of inorganic and/or organic origin,these various compounds acting in complete synergy.

The invention also relates to the process for the preparation of saidcompositions and for the application of said compositions at the surfaceof freshly placed or freshly demolded mortars and/or concretes.

Finally, the invention relates to the use of said compositions in theform of a layer, deposited on the surface of freshly placed or freshlydemolded mortars and/or concretes, applied in order to provide waterretention within mortars and/or concretes during their setting and theirhardening, and to maintain therein an amount of water sufficient for thepurposes of preventing, or at least limiting, phenomena of shrinkagewith the appearance of cracks, and to retain, in these mortars and/orconcretes, the desired characteristics, such as, for example, a very lowshrinkage, good water impermeability, excellent frost resistance andothers, and thus to provide said mortar and/or concrete surfaces withhigh adhesiveness for the finishing materials intended to cover them,such as plaster, ceramics, paints, various coatings or others, withoutprior removal of said layer.

STATE OF THE ART

The incorporation of water into a medium comprising a hydraulic binderamong its constituents, such as mortars and/or concretes, brings aboutirreversible reactions in which needle-shaped crystals are formed byhydration of the inorganic salts present, which are initially amorphousand anhydrous, and results in the setting of the hydraulic binder by theinterpenetration of these needle-shaped crystals, thickening andstrengthening and then hardening the medium comprising them.

As the use of hydraulic binder or of media comprising it takes place inthe open air and as, in addition, the setting reaction is exothermic, itis known that a fraction of the water incorporated in the binder or inthe medium comprising it evaporates and that there is consequently alack of water for ensuring the continuation of the crystallizationduring the hardening stage, during which the hydraulic binder or themedium comprising it acquires all the desired mechanicalcharacteristics, such as, for example, a low degree of shrinkage,impermeability to water, resistance to low temperatures and highmechanical strength.

For a long time, one of the commonest failings has been the appearanceof cracks related to the shrinkage of the mortar or concrete comprisinga hydraulic binder during hardening, this shrinkage very frequentlybeing the consequence of a loss of water by evaporation when the mediumcomprising the hydraulic binder, in particular mortars and concretes, issubjected to the simultaneous action of the exothermicity developed bythe setting, of its exposure to the sun and of the existence of naturaldrying ventilation.

Various means have been used to compensate for or prevent loss byevaporation of a portion of the water incorporated in media comprising,among their constituents, a hydraulic binder, such as, in particular,mortars and concretes.

According to a first type of means, a conventional and long-standingtreatment for preventing the evaporation of water consists in keepingthe surface of freshly placed or freshly demolded mortars and/orconcretes in contact with surroundings which are as permanently aspossible humid during the setting time by the creation of a sustainedfilm of water or by the use of a textile substrate with a spongy naturewhich is impregnated with water or by the use of a polymer film unwoundover said surface to prevent evaporation, creating a greenhouseenvironment between the surface to be protected and the atmosphere.

However, this first type of means is not much used today on buildingsites or sites involving substantial renovation as it requires closemonitoring and, consequently, takes up manpower, rendering itparticularly expensive.

According to another type of means, an adherent and protectivecontinuous film is created on the surface of the mortars and/orconcretes by depositing thereon, by spraying or by brushing, a paraffinwax, alone or in combination with at least one hydrocarbon resin, insolution in an organic solvent, to form a barrier between said surfaceand the surrounding atmosphere and thus to prevent the occurrence of thephenomenon of evaporation of the water present in the composition of themortars and/or concretes.

However, there are several disadvantages to this type of means which canrender its use unacceptable. Mention may be made, among the mostsignificant disadvantages, for example, of:

-   -   the use of organic solvents, which constitutes a danger to the        environment, in particular when solvents with a carcinogenic        nature, such as benzene, toluene and other aromatic solvents, or        halogenated solvents, such as chlorinated hydrocarbons        (trichloroethylene or perchloroethylene), are used,    -   the incompatibility of organic solvents with water, which makes        it necessary to wait, in order to create the protective film on        the surface to be protected, for the moisture content of this        surface to be as low as possible, said film being created once        the setting of the mortars and/or concretes is already well        initiated. Consequently, the film is created too late and often        ineffectively since the evaporation of the water, which has to        be prevented, is also underway, indeed even well advanced.

Finally, according to another type of means, a continuous and protectivefilm is created on the surface of the freshly placed or freshly demoldedmortars and/or concretes by depositing thereon, by spraying or bybrushing, an emulsion in water of a paraffin wax, alone or incombination with at least one other compound, such as a hydrocarbonresin, a hydrocarbon oil and/or a pigmentary filler and/or fattyalcohols and/or fatty acids, in order to form, at an early stage at thebeginning of the setting, a barrier between said surface and thesurrounding atmosphere and to thus prevent the occurrence of thephenomenon of evaporation of the water involved in the composition ofthe mortars and/or concretes. In common with the mortars and concretes,this emulsion comprises water, which renders this type of evaporationcontrol treatment compatible and particularly advantageous.

However, the last two types of means used to treat the surfaces offreshly placed or freshly demolded mortars and/or concretes, in order toprovide the water retention necessary for their setting and for theirhardening, result in new disadvantages which constitute major failingswhen the surfaces thus treated are to be covered by finishing materials,such as, for example, plaster finishes, paints, renderings, ceramics orothers.

Specifically, it is apparent that:

-   -   the poorly controlled, incomplete and uneven decomposition of        the film created to form a barrier to evaporation, which        decomposition is brought about by the action of ultraviolet        radiation, leaves large amounts of residues of said protective        film adhering to the treated surface;    -   residues of the decomposed film adhering to the treated surface        reduce the adhesiveness at said surface of the finishing        materials, such as plaster finishes, paints, adhesives for        ceramics and others, when the finishing work begins.    -   in order to obtain satisfactory adhesion of the finishing        materials at said surface thus treated, it turns out to be        absolutely necessary to brush, scrape or sand down said surface        before beginning the finishing work, in order to remove        therefrom the protective film residues still adhering.

Coming under the final type of means, numerous documents disclosecompositions as an emulsion in water intended for the treatment of thesurfaces of freshly placed or freshly demolded mortars and/or concretes,the function of which is to prevent the evaporation of the waterinvolved in the formation of said mortars and concretes.

U.S. Pat. No. 2,928,752 discloses aqueous emulsions intended for theprotection of the surfaces of mortars and/or concretes during thesetting period and then at the beginning of the hardening period, inorder to prevent water evaporation, these emulsions comprising aparaffin wax, a reaction product prepared from ethylene oxide andunsaturated oleyl alcohol, an amine salt of a long-chain C₁₂ to C₁₈carboxylic acid, a long-chain C₁₂ to C₂₀ fatty alcohol and, optionally,a small amount (0 to 10% by weight) of a mineral oil intimately mixed,when it is present, with the molten paraffin wax, in order to renderthis paraffin wax more maleable.

These compositions, the essential disadvantage of which is that of beingrendered complex by the number of components of which they are formed,are supposed to be rendered more adhesive to the surfaces of mortarsand/or concretes to be protected from the evaporation of the water byvirtue of the presence of the amine functional group, which has anaffinity for the components of the mortars and/or concretes.

However, these coating compositions for protecting the surfaces of themortars and/or concretes in order to prevent the evaporation of thewater have disadvantages which, in addition to the complexity of theirformulations, are, for example:

-   -   the presence of alcohol or acid functional groups in said        compositions, which presence can result in the occurrence of a        setting delay at the surface of the treated mortar and/or        concrete and/or can optionally result in a more or less        pronounced deactivation of the mortar and/or concrete, depending        on the amounts of alcohol or acid functional groups present;    -   a water retention which is often inadequate in surface-treated        mortars and/or concretes, resulting in phenomena of cracking;    -   lack of adhesion of the finishing materials applied to the        surfaces treated by means of said compositions.

U.S. Pat. No. 3,189,469 discloses aqueous emulsions with a reflectivecapacity when they are applied to the surfaces of freshly placed orfreshly demolded mortars and/or concretes intended to be protected fromthe evaporation of the water during the setting period and the beginningof the hardening, which are composed, in combination, of a hydrocarbonwax, which is essentially paraffin wax, in a proportion of 15 to 50% byweight, of a product of the reaction between saturated and unsaturatedC₁₂ to C₂₂ fatty acids and an alkaline agent, such as an alkalinehydroxide or an amine, in a proportion of 1 to 10% by weight of saidproduct, of an inorganic pigment with a high reflecting power, such asTiO₂, CaCO₃, ZnO or MgCO₃, in a proportion of 1 to 10% by weight, and ofa nonionic and anionic dispersing agent, in a proportion of 1 to 3% byweight.

These compositions are supposed to be rendered more adherent to thesurfaces of mortars and/or concretes to be protected from theevaporation of the water by virtue of the presence of the aminefunctional group or of the alkaline compound, which neutralize the acidfunctional group of the saturated and unsaturated fatty acids, thisamine functional group and this alkaline compound having the advantageof having an affinity with regard to the components of the mortarsand/or concretes.

Despite this advantage, there are disadvantages to these coatingcompositions for protecting the surfaces of mortars and/or concretes inorder to prevent the evaporation of the water during their setting andtheir hardening, which are, for example:

-   -   the complexity of their formulation;    -   the presence of acid functional groups introduced by the fatty        acids which can result in the appearance of a setting delay at        the surface of the treated mortars and/or concretes and/or which        may possibly result in more or less pronounced deactivation of        the mortar and/or concrete, depending on the amounts of acid        functional groups present;    -   the presence of a pigment, such as TiO₂, for providing said        compositions with a high reflectivity, which can help in        reducing the evaporation of the water at the surface of the        mortars and/or concretes during the setting and the hardening;    -   a water retention to be regarded as inadequate;    -   lack of adhesion of the finishing materials applied to the        treated surfaces, a consequence of the presence in said        compositions of acid functional groups.

U.S. Pat. No. 4,239,540 discloses an aqueous emulsion for the protectionof the surfaces of freshly placed or freshly demolded mortars and/orconcretes, in order to prevent the evaporation of water during thesetting period and then the hardening period, which is composed of aparaffin wax (18.2% by weight), of a mixture of oils formed of a coconutoil (4.2% by weight), of a soybean oil (3.3% by weight), of a linseedoil (4.2% by weight), of stearic acids (3.4% by weight), of hexacosanoicacid (1.6% by weight), of water (62.5% by weight) and of an ethylcyanuric ester (2.6% by weight) as emulsifying agent.

This aqueous emulsion with a very specific composition, which might seemadvantageous for the treatment, for preventing the evaporation of thewater, of the surfaces of mortars and/or concretes during the settingand the hardening, does not appear to be able to be made use of becausethe results stated show that it has a very low capability of being awater retainer (0.027 to 0.038 g of water/cm²). In addition, thisaqueous emulsion comprises organic acids, the acid functional groups ofwhich can result in:

-   -   a more or less pronounced deactivation of the mortar and/or        concrete on which said emulsion is deposited, bringing about a        loss in adhesion for the finishing materials applied to the        treated surfaces;    -   the appearance of a setting delay at the surface of said treated        mortars and/or concretes;    -   lack of adhesion of the finishing materials applied to the        treated surfaces.

U.S. Pat. No. 4,495,319 discloses a method for the preparation of anemulsion intended for the curing treatment of the surfaces of freshlyplaced or freshly demolded mortars and/or concretes in order to preventthe evaporation of the water present at the surface of said mortarsand/or concretes during the setting period and the hardening period.This emulsion is formed from hydrocarbon resin, from paraffin wax andfrom emulsifying agents obtained from fatty acids and morpholine. Thepresence of pigments, such as TiO₂, and/or of an inorganic filler, suchas CaCO₃, used as pigment, is also disclosed.

However, this emulsion exhibits the disadvantage of being composed ofmaterials which are solid at ambient temperature, that is to say ofparaffin wax and of hydrocarbon resin in the solid state, making itdifficult to prepare the emulsion and resulting in an emulsion which maybe unstable and in a fairly disappointing use as protective film againstevaporation of the water from the surface of freshly placed or freshlydemolded mortars and/or concretes: the ability of this emulsion toprevent loss of water by evaporation appears to be inadequate, even ifthis emulsion were to comprise a pigment for increasing the reflectancethereof and, consequently, for attempting to increase its effectiveness.Furthermore, another disadvantage is revealed in the appearance of alack of adhesion of the finishing materials applied to the treatedsurfaces.

Patent Application FR 2 691 962 A discloses aqueous emulsions formed ofparaffin wax and of natural or synthetic hydrocarbon resins, inparticular pine resins, which are intended to be applied to the surfacesof freshly placed or freshly demolded mortars and/or concretes in orderto limit the evaporation of the water during the setting period and thebeginning of the hardening. These emulsions are composed of materialswhich are solid at ambient temperature. However, the use of theseemulsions as protective film against the evaporation of the water fromthe surface of freshly placed or freshly demolded mortars and/orconcretes does not appear to be satisfactory with regard to the resultsstated (52.8% after two hours, much less than the 85% of the paraffinwax alone) and is the cause of the lack of adhesion for the finishingmaterials applied subsequently to the treated surfaces.

Another document, DE 197 35 431 C, discloses an aqueous treatmentproduct for wet concrete, characterized by a mixture composed of 10.0 to30.0% by weight of aqueous butyl acrylate copolymer dispersion devoid ofplasticizer or of aqueous methacrylate copolymer dispersion (a), of 1.0to 10.0% by weight of solution of sodium and potassium silicates, of 0.1to 2.0% by weight of antifoaming agent, of 0.2 to 4.0% by weight ofthixotropic agent, of 0.1 to 10.0% by weight of micronized polyethylenewax and of 88.6 to 44.0% by weight of water, for producing a coveringwhich is impermeable to water and to water vapor on the surface of freshconcrete and on the surface of green concrete of concrete buildingcomponents.

This aqueous treatment product for wet concrete forms awater-impermeable covering which adheres to the surfaces of freshconcretes to be protected from the evaporation of the water and protectsthem from drying and from the damage inflicted by torrential rain.

However, this aqueous treatment product, which forms a covering whichprotects the surfaces of fresh concretes in order to prevent theevaporation of water during their setting and their hardening, does notexhibit any difficulty with regard to removal or cleaning once thecovered concrete has completely hardened, so as to re-expose the rawconcrete surface.

This ease of removal of the protective covering, once the concrete hashardened, indicates a low mechanical strength of said covering duringadhesion of the finishing materials to the treated surfaces.

Consequently, it appears necessary to remove or to eliminate thisprotective covering, created to form a barrier to evaporation, beforebeginning the finishing work on the raw concrete surface in order toobtain significant adhesion between finishing materials intended tocover it and the hardened concrete.

SUBJECT MATTERS OF THE INVENTION

As revealed by the state of the art, the aqueous emulsions provided andintended to be applied to the surfaces of freshly placed or freshlydemolded mortars and/or concretes in order to limit the evaporation ofthe water from the beginning of setting exhibit numerous disadvantages.

This is why the subject matters assigned to the invention are many andmultifarious, as are the abovementioned disadvantages, in order tointroduce at least one improvement thereto.

The various subject matters assigned to the invention are the creationof organic compositions which are aqueous emulsions possessing essentialcharacteristics which are necessary and desired in order for them to beapplied to the surfaces of freshly placed or freshly demolded mortarsand/or concretes and, once applied, for them to limit and preferablyprevent the evaporation of the water, which is absolutely necessary fortheir setting and for their hardening.

Some of the essential characteristics assigned to the aqueous emulsionsaccording to the invention are specified by way of illustration. Thus,the aqueous emulsions according to the invention:

-   -   must be formed of the paraffin wax usually present and of other        hydrocarbon compounds which can be emulsified in an aqueous        medium;    -   must not comprise compounds capable of deactivating the surfaces        of the mortars and/or concretes receiving them, which would        weaken their adhesiveness for the finishing materials which        subsequently cover these surfaces;    -   must be devoid of compounds capable of retarding, at the        surface, the setting of the mortars and/or concretes which are        covered with them;    -   must be easy to prepare and stable after their preparation;    -   must be easy to apply to the surfaces to be treated, preferably        by spraying;    -   must be applied very rapidly to the surfaces of freshly placed        or freshly demolded mortars and/or concretes in order to        actually ensure retention of the composition water;    -   must be able to provide said treated surfaces with greater        protection against the evaporation of the water than that of the        paraffin wax alone, by formation of a film which is a barrier to        said evaporation;    -   must not comprise compounds which are particularly harmful to        the environment;    -   must be devoid of carcinogenic compounds, such as, in        particular, benzene, toluene and xylene;    -   must also form, at the surface of freshly placed or freshly        demolded mortars and/or concretes, not only a film which is a        barrier to the evaporation but also a film which adheres        strongly to the treated surface after said mortars and/or        concretes have set and hardened;    -   must make possible, whether or not there is even partial        decomposition of the barrier film, much improved adhesion for        the finishing materials applied to the surfaces covered with the        film, without it being necessary to remove it from said surfaces        before these surfaces are covered with the finishing materials.

SUMMARY OF THE INVENTION

According to the invention, the aqueous emulsions intended to be appliedto the surfaces of freshly placed of freshly demolded mortars and/orconcretes in order to prevent the evaporation of the water from thebeginning of setting and to create, on said surfaces, high adhesivenessfor the finishing materials to be deposited thereon at least partiallyremove the disadvantages displayed in the state of the art and, inaddition, introduce substantial improvements not existing in the meansdescribed to date, in order to render the emulsions particularlyeffective in the role which is assigned to them.

According to the invention, the compositions intended to be applied tothe surfaces of freshly placed or freshly demolded mortars and/orconcretes in order both to prevent the evaporation of the water presentin said mortars and concretes, which is necessary for their setting andthen for their hardening, and to create, on said treated surfaces, highadhesiveness for the finishing materials intended to cover them areprovided in the form of aqueous emulsions comprising at least oneparaffin wax (a), alone or in combination with at least one otherhydrocarbon compound (b) and/or hydrocarbon compound (c), such as ahydrocarbon wax or oil which is solid or liquid at ambient temperature,and also comprising at least one latex formed of a colloidal aqueousemulsion of at least one polymer and at least one pulverulent filler ofinorganic and/or organic origin.

The term “hydrocarbon compound” should be understood as meaning anyorganic compound essentially composed of carbon and hydrogen and whichcan also comprise at least one of the elements from oxygen, nitrogen,sulfur and phosphorus.

Also according to the invention, the compositions intended to be appliedto the surfaces of freshly placed or freshly demolded mortars and/orconcretes in order both to prevent the evaporation of the water presentin said mortars and/or concretes, which is necessary for their settingand then for their hardening, and to create, on said treated surfaces,high adhesiveness for the finishing materials intended to cover them areprovided in the form of aqueous emulsions comprising, according to anovel combination of means, at least one paraffin wax (a), alone or incombination with at least one hydrocarbon compound (b) and/or at leastone other hydrocarbon compound (c) different from the hydrocarboncompound (b), at least one latex (d) formed of a colloidal aqueousemulsion of at least one polymer, and at least one pulverulent filler ofinorganic and/or organic origin (e).

More particularly, and according to the invention, the compositionsintended to be applied to the surfaces of freshly placed or freshlydemolded mortars and/or concretes, before the beginning of setting, forthe purpose of rendering them both synergistic, in order to prevent theevaporation of the water necessary for their setting and for theirhardening and to create, on said surfaces, high adhesiveness of thefinishing materials, are provided in the form of an aqueous emulsioncomprising at least one paraffin wax, alone or in combination with atleast one other hydrocarbon compound, and are characterized in that theyare composed:

-   a) of at least one paraffin wax of petroleum or synthetic origin    including, as a mixture, saturated and unsaturated aliphatic    hydrocarbons of general formulae C_(n)H_(2n+2) and C_(n)H_(2n) for    which n is at least equal to 30 and for which the melting point is    between 40° C. and 75° C.;-   b) and/or of at least one linear and/or cyclic hydrocarbon oil of    aliphatic and/or naphthenic origin which are hydrocarbon chains,    alone or as a mixture, of general formulae C_(n)H_(2n+2) and    C_(n)H_(2n) for which n is less than 30, in the liquid state at    ambient temperature;-   c) and/or of at least one hydrocarbon compound different from (b)    which can be an oil formed of at least one ester resulting from the    condensation reaction of a saturated and/or unsaturated fatty acid    with an alcohol having from one to five hydric functional groups;-   d) of at least one latex formed of a colloidal aqueous emulsion of    at least one polymer;-   e) of at least one pulverulent filler of inorganic and/or organic    origin.

DETAILED DESCRIPTION OF THE INVENTION

The compositions according to the invention, intended to be applied tothe surfaces of freshly placed or freshly demolded mortars and/orconcretes before the beginning of setting in order to prevent theevaporation of the water necessary for their setting, are:

-   -   aqueous emulsions of paraffin wax, of hydrocarbon compounds, in        particular oils, of latexes and of inorganic fillers;    -   synergistic with regard to the water retention and with regard        to the increase in the adhesiveness through their components and        the relative amounts of these various components involved;    -   stable on storage, even long-term storage.

According to the invention, the compositions intended both, by theirpresence on the surfaces of freshly placed or freshly demolded mortarsand/or concretes, to prevent the evaporation of the water and to bestow,on said treated surfaces, improved adhesiveness for the finishingmaterials intended to cover them are aqueous emulsions based on paraffinwax. In point of fact, an emulsion is, by definition, a dispersion of aliquid compound, or compound rendered liquid, in another liquidcompound. In the case of the invention, the paraffin compound, referredto as component (a), which, at ambient temperature, is awater-immiscible solid compound, is rendered liquid by a slight rise intemperature and is simultaneously dispersed in water brought to anappropriate temperature for the formation of an emulsion with vigorousstirring. However, the paraffin compound may already exist in the formof a commercial aqueous emulsion and can be used in this state for thepreparation of the compositions according to the invention.

The paraffin wax can be employed in the context of the invention aloneor in combination with at least one other hydrocarbon compound for thepreparation of the abovementioned emulsion.

Said paraffin wax is chosen from the group consisting of alkanes and/oralkenes, taken alone or as a mixture, which are saturated and/orunsaturated hydrocarbons of petroleum or synthetic origin of generalformulae C_(n)H_(2n+2) and C_(n)H_(2n) for which n is at least equal to30 and preferably between 30≦n≦120 and for which the melting point isbetween 40° C. and 75° C. and preferably between 50° C. and 70° C.

From the value of “n” and the relative amounts of alkanes and alkenesforming the paraffin wax employed, the density of said paraffin wax isbetween 0.85 and 0.95 and preferably between 0.88 and 0.92.

To prevent the emulsion produced by the dispersion of the moltenparaffin wax in water from giving a coalescence effect, that is to saythe paraffin wax and the water from separating into two layers, anemulsifying agent which facilitates the stability of the emulsion can beintroduced into said emulsion, this agent being active in a capillarysense and being positioned, owing to an adsorption phenomenon, at thesurface which separates the microdroplets of paraffin wax and water,these being surrounded by an interfacial film.

Such an emulsifying agent can be anionic and/or nonionic in nature. Itcan be chosen from well-known emulsifying products, such as C₈ to C₂₂fatty acids neutralized by an amine, in particular triethanolamine;sulfonated or phosphonated compounds; fatty alcohols; sorbitan esters;ethylene oxide/propylene oxide copolymers; or others. Such emulsifyingagents are, for example, sold by Seppic under the name of Simulsol,Montane or Montanox and by Lambert-Rivière under the name of Syntopon.

Emulsions formed of paraffin wax in water, the paraffin wax of whichcorresponds to the abovementioned characteristics, are sold, forexample, by Exxon-Mobil Oil under the trade names Mobilcer 115, Mobilcer730, Mobilcer C, Prowax 397 and Mobilwax 2370 or by SuddeutscheEmulsions Chemie under the trade names Wukonil KN 50, Wukonil LP 50 andWukonil LP 38 or by Michelman under the trade name ME91240E.

The compositions according to the invention can also comprise, inaddition to the paraffin wax, at least one other hydrocarbon compound inthe solid or liquid state at ambient temperature which can be chosenfrom the group consisting of natural or synthetic hydrocarbon waxesand/or oils, such as the oils pine oil or rosin oil, “vegetable” oils,such as rapeseed oil, sunflower oil or palm oil, or “mineral” oils, suchas paraffinic or naphthenic oils.

Preferably, the compositions according to the invention can comprise, asanother hydrocarbon compound, at least one hydrocarbon oil, referred toas component (b), of petroleum origin of aliphatic and/or naphthenictype and, in the latter case, resulting from the series of thecyclopentanes and cyclohexanes, which are saturated and/or unsaturatedhydrocarbons, present alone or as mixtures, of general formulaeC_(n)H_(2n+2) and/or C_(n)H_(2n) for which n is less than 30 and ispreferably between 10 and 25, these hydrocarbon oils being in a liquidstate at ambient temperature.

All these oils have, under standard temperature and pressure conditions,a kinematic viscosity of between 5 and 500 mm²/s and a density ofbetween 0.83 and 0.97.

Mention may be made, as hydrocarbon oil of aliphatic and/or naphthenicorigin, by way of example, of the oil of Neutral type, sold byExxon-Mobil, which has a kinematic viscosity of 20 mm²/s, or the oilsHMVIP 30 and HVI 65, sold by Shell, and 60 Neutral, 80 Neutral and 150Neutral, sold by Exxon-Mobil.

The compositions according to the invention can also comprise, incombination with or as replacement for the hydrocarbon compound (b), atleast one other hydrocarbon compound different from (b) which can be anoil which is liquid at ambient temperature, which can be formed of anester resulting from the condensation reaction of a saturated and/orunsaturated fatty acid with a mono-, di- or trihydric alcohol,constituting the component (c).

The fatty acids participating in the formation of the ester according tothe invention are saturated and/or unsaturated and branched orunbranched hydrocarbon compounds, for example originating from thehydrolysis of oils and of fatty substances, preferably carrying a singlecarboxylic acid functional group. They are generally chosen, forexample, from the group consisting of C₈ to C₂₄ fatty acids, such as,for example, caprylic, capric, lauric, myristic, palmitic, stearic,arachidic, behenic, lignoceric, palmitoleic, oleic, gadoleic, erucic,linoleic, linolenic and isolinolenic acids.

The alcohols participating in the formation of the ester according tothe invention are C₂ to C₂₀ hydrocarbon compounds comprising from one tofive alcohol functional groups. These alcohols can be chosen from thegroup consisting of alkanols and/or alkenols, such as, for example,ethanol, propanol, butanol, pentanol, stearyl alcohol or oleyl alcohol,when it is a matter of using a monohydric alcohol, from the groupconsisting, for example, of propanediol, butanediol, pentanediol,hexanediol, heptanediol, octanediol, nonanediol, decanediol,undecanediol and dodecanediol, and other dihydroxyalkanes or -alkenes,when it is a matter of using a dihydric alcohol, and/or from the groupconsisting of glycerol, butanetriol, pentanetriol, hexanetriol,heptanetriol, octanetriol, nonanetriol, decanetriol, undecanetriol,dodecanetriol and other trihydroxyalkanes or -alkenes, when it is amatter of using a trihydric alcohol, or propane-1tri-2di-ol, when it isa matter of using an alcohol comprising five hydric functional groups.

The compositions according to the invention also comprise, incombination with the component (a), which is the paraffin wax, andoptionally in combination with the other hydrocarbon compounds, such asthe components (b) and/or (c), another component (d) formed of at leastone latex which is composed of a colloidal aqueous emulsion of at leastone polymer and/or copolymer chosen from the group consisting ofhomopolymers of acrylic acid, of methacrylic acid and of the esters ofthese acids, the ester group of which is a C₁ to C₁₂ alkyl group, suchas methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl,2-ethylhexyl, 2-ethylbutyl or 2-heptylhexyl, copolymers of acrylic acid,of methacrylic acid and/or of the esters of these acids, the ester groupof which is a C₁ to C₁₂ alkyl group, copolymers of vinyl and of acrylicacid or of methacrylic acid, copolymers of vinyl and of ester groups ofwhich are C₁ to C₁₂ alkyl groups, copolymers of acrylic or methacrylicacid, copolymers of acrylic acid or of methacrylic acid and of acrylicor methacrylic esters, styrene/acrylic or methacrylic copolymers,copolymers of ethylene and of vinyl acetate, copolymers of ethylene andof acrylic or methacrylic acid, acrylic/urethane copolymers andstyrene/butadiene copolymers.

These various latexes comprise from 10% to 80% by weight of the polymerand/or copolymer employed in the context of the invention.

The compositions according to the invention also comprise, incombination with the component (a), which is the paraffin wax, and thecomponent (d), which is the latex, and optionally in combination with atleast one other hydrocarbon compound, such as the components (b) and/or(c), at least one pulverulent filler of inorganic or organic origin, themedian particle size of which is between 1 μm and 100 μm and thedistribution of which is between 0 μm and 300 μm.

The pulverulent inorganic filler is preferably chosen from the groupconsisting of calcium carbonate, clays and kaolin, alumina, microsilica,silica fume and barium sulfate, used alone or as a mixture.

This pulverulent inorganic filler has a BET specific surface of at least1 m²/g and preferably of between 20 m²/g and 700 m²/g, it beingspecified that the BET specific surface of this pulverulent inorganicfiller increases in effectiveness as said specific surface increases.

The pulverulent organic filler is preferably chosen from the groupconsisting, for example, of the powders formed of polymers, copolymers,elastomers, thermoplastics or thermosets, employed alone or as amixture. The pulverulent inorganic and organic fillers can be employedalone or as a mixture.

The compositions according to the invention, produced by means of thecomponents (a), (b) and/or (c), (d) and (e), which are:

-   -   paraffins of petroleum or synthetic origin including, as a        mixture, saturated hydrocarbons of general formula C_(n)H_(2n+2)        and/or unsaturated hydrocarbons of general formula C_(n)H_(2n)        with n≧30;    -   at least one other hydrocarbon compound which can be a linear        and/or cyclic hydrocarbon oil of aliphatic and/or naphthenic        origin which are hydrocarbon chains, alone or as a mixture, of        general formulae C_(n)H_(2n+2) and C_(n)H_(2n) for which n is        less than 30;    -   optionally at least one other hydrocarbon compound chosen from        the group of the hydrocarbon waxes and/or oils;    -   at least one latex formed of a colloidal aqueous emulsion of at        least one polymer and/or copolymer;    -   and at least one pulverulent filler of inorganic or organic        origin,        are synergistic compositions intended to be applied to the        surfaces of freshly placed or freshly demolded mortars and/or        concretes in order to prevent the evaporation of the water        necessary for their setting and for their hardening, the        synergistic nature of which is attested to by their ability both        to prevent the evaporation of water and to provide the treated        surfaces with a much improved adhesion for the finishing        materials.

This synergistic character is achieved once the various components ofthese compositions, as aqueous emulsions, are present, as percentages ofactive materials (or dry matter), in a proportion of:

-   -   component (a) or paraffin wax: from 2% to 90% by weight,        preferably from 5% to 60% by weight, very preferably from 5% to        40% by weight;    -   component (b) or hydrocarbon compound: from 0% to 90% by weight,        preferably from 8% to 40% by weight, very preferably from 9% to        30% by weight;    -   component (c) or hydrocarbon compound other than the compound        (b): from 0% to 90% by weight, preferably from 10% to 50% by        weight, very preferably from 15% to 40% by weight;    -   component (d) or latex formed of at least one polymer and/or        copolymer as an emulsion in water: from 10% to 45% by weight and        preferably from 15% to 35% by weight;    -   component (e) or pulverulent inorganic and/or organic filler:        from 0.01% by weight to 10% by weight and preferably from 0.02%        by weight to 5% by weight;    -   water: q.s. for 100% by weight.

Preferably, when the components (b) and/or (c) are chosen fromhydrocarbon compounds which are liquid at ambient temperature:

-   -   the component (b) is chosen from linear and/or cyclic        hydrocarbon oils of aliphatic and/or naphthenic origin which are        hydrocarbon chains, alone or as a mixture, of general formulae        C_(n)H_(2n+2) and C_(n)H_(2n) for which n is less than 30;    -   the component (c) is chosen from oils formed of at least one        ester resulting from the condensation reaction of a saturated        and/or unsaturated fatty acid with a mono-, di- or trihydric        alcohol.

The compositions according to the invention, produced by means of thecomponents (a), (b) and/or (c), (d) and (e), are in a synergistic statewhen the compositions are applied to the surfaces of freshly placed orfreshly demolded mortars and/or concretes since they simultaneouslyprevent evaporation of the water, which is necessary for their settingand for their hardening, far better than the emulsions formed ofparaffin waxes alone or of oils alone and provide said surfaces thustreated with a much improved adhesiveness of the finishing materialswhich have to cover them.

This synergistic character is achieved once the various components ofthese aqueous compositions or emulsions are present, as percentages ofactive materials (or dry matter), in a proportion of:

-   -   component (a) or paraffin wax: from 2% to 90% by weight,        preferably from 5% to 60% by weight, very preferably from 5% to        40% by weight;    -   component (b) or hydrocarbon compound: from 5% to 90% by weight,        preferably from 8% to 40% by weight, very preferably from 9% to        30% by weight;    -   component (c) or oil formed of at least one ester: from 5% to        90% by weight, preferably from 10% to 50% by weight, very        preferably from 15% to 40% by weight;    -   component (d) or latex formed of at least one polymer and/or        copolymer as an emulsion in water: from 10% to 45% by weight and        preferably from 15% to 35% by weight;    -   component (e) or pulverulent inorganic and/or organic filler:        from 0.01% by weight to 10% by weight and preferably from 0.02%        by weight to 5% by weight;    -   water: q.s. for 100% by weight.

Furthermore, the ratio by weight, as dry active material, of the totalof the components (b) and/or (c) and of the paraffin wax present in theaqueous emulsions of the compositions according to the invention must beat least equal to 0.25, may preferably be at least equal to 0.63 andvery preferably may vary between 0.64 and 9.

The compositions according to the invention, in the form of aqueousemulsions, have a dry matter content which can vary, in general, from10% to 60% by weight but preferably from 30% to 50% by weight.

Said compositions in the form of aqueous emulsions are used by sprayingover the surfaces to be protected, the working load deposited per unitof surface area being between 50 g/m² and 150 g/m² in order to achieve awater retention at least equal to 90% by weight of the amount of waterlost by the untreated control.

The compositions according to the invention, which are aqueousemulsions, are stable on storage, even prolonged storage.

Furthermore, when these compositions according to the invention areapplied, they prove to have a very high effectiveness as, in contrast tothe compositions of the state of the art, they require a far smalleramount of dry active material deposited per m² to be protected, thusrendering them both very effective and very economical.

The invention also relates to a process for the preparation of thecompositions for protection against the evaporation of water from thesurfaces of freshly placed or freshly demolded mortars and/or concreteswhich comprises the successive stages of introduction of the variouscomponents into a preparation region subjected to very vigorousstirring, the contents of which can be heated and/or cooled, thesestages being:

-   i) the introduction into said region, according to the calculated    amount, of the water necessary to create the emulsion and then    optionally the introduction of an emulsifying agent, this first    mixture being subjected to vigorous stirring during the time needed    to produce a homogeneous medium;-   ii) the introduction, according to the calculated amounts, of a    mixture of the components (b) and/or (c), forming a second mixture,    which is subjected to the same vigorous stirring during the time    needed to produce the first emulsion;-   iii) the introduction, according to the calculated amount and with    gentle stirring, of the paraffin wax into the mixture resulting from    ii):    -   heated beforehand to a temperature sufficient to cause the        paraffin wax to melt and to convert the paraffin wax into the        emulsion state, when said paraffin wax is introduced in the form        of a very fine powder; or    -   at ambient temperature, when the paraffin wax is introduced in        the form of an aqueous emulsion;    -   and maintenance of gentle stirring during the prolonged time        needed to form the emulsion, with optional cooling of the        emulsion;-   iv) the introduction into the mixture resulting from iii), according    to the calculated amount and with gentle stirring, of the component    (d), which is the latex, subjected to gentle stirring during the    time needed to produce the aqueous emulsion formed of the components    (a), (b), (c) and (d);-   v) the introduction into the emulsion resulting from iv), according    to the calculated amount and with vigorous stirring, of the    component (e), which is the pulverulent inorganic and/or organic    filler;-   vi) and then subjection of the emulsion resulting from the second    mixture converted to an aqueous emulsion resulting from v) to gentle    stirring for a prolonged time in order to homogenize the aqueous    emulsion formed comprising all the components.

This final gentle stirring time of stage iv) or vi) can reach 90minutes, indeed even exceed it, in order to obtain an emulsion having adrop size of less than or equal to one micron.

The invention will be better understood by virtue of the variousexamples below, presented by way of illustration without impliedlimitation.

In the context of these examples, which illustrate the ability of thecompositions according to the invention both to prevent the evaporationof the water from freshly placed or freshly demolded mortars and/orconcretes and to provide the surfaces treated by said compositions witha much improved adhesiveness for the finishing materials covering them,the adhesion tests to which said compositions are subjected are definedbelow:

Manufacture of Concrete, One of the Surfaces of Which is Treated by theComposition According to the Invention

An admixture-comprising self-placing concrete with the followingcomposition as % by weight:

aggregate (reference) 78.5% hydraulic binder (reference) 12.5% admixture1.5% water 7.5%is manufactured. The spreading, measured with an 1100 cm³ cone, isbetween 34 and 37 cm. The concrete thus produced is introduced into40×40×8 cm molds and the surface of the concrete is floated to produce asmooth surface.

Concrete slabs with the same composition are thus prepared.

Deposition on the Smooth Concrete Surface of the Composition Accordingto the Invention

The treatment composition is sprayed at the rate of 100 to 200 g/m² oversaid free surface of a prepared concrete slab.

Another concrete slab, produced at the same time as the first, forms thereference surface, devoid of any surface treatment by the compositionaccording to the invention.

Covering the Surfaces of the Concrete Slabs Treated by the CompositionAccording to the Invention and Untreated Slabs

Stoneware tiles are adhesively bonded to the surface of the slabstreated and not treated with the composition according to the invention,two weeks after the manufacture of said slabs.

The tiles are adhesively bonded to the surface of the slabs by means ofa tiling adhesive mortar (Lanko 554 adhesive, sold by Lafarge Mortiers).

This adhesive mortar is applied according to the procedure whichconsists in using:

-   -   a trowel with 5×5×5 square teeth for spreading the adhesive        mortar,    -   a load of 2 kg deposited on the tiles during adhesive bonding,        10 tiles being adhesively bonded per slab,    -   a drying time of the adhesive mortar which is 7 days.

Adhesive Bonding to the Ceramic Tiles of the T-Pieces Used for TearingOff

The T-pieces used for tearing off are adhesively bonded using the Lanko532 adhesive one day before tearing off the tiles.

Tearing Off the Tiles Via the T-Pieces

The tiles are torn off via the T-pieces using a tensile testing device

EXAMPLE 1

This example relates to curing compositions devoid of latexes and ofinorganic fillers.

Compositions were prepared in the form of an aqueous emulsion, whichcompositions are formed of:

-   -   paraffin wax: Redesmol 300 (registered trademark), sold by        Repsol in the form of an aqueous emulsion with a solids content        of 63%, and Mobilcer 115 and Mobilcer 730 (registered        trademarks), sold by Mobil in the form of aqueous emulsions with        solids contents of 45% and 50% by weight respectively;    -   oil of type (b), which is a paraffinic oil with a low viscosity        equal to 20 mm²/s, sold by Exxon-Mobil under the trade name 60        Neutral;    -   water: q.s. for 100% by weight.

The method of preparation was as follows:

Firstly, the amount of water necessary for the preparation of thecomposition according to the invention by the formation of an aqueousemulsion is introduced into an appropriate reactor.

When the paraffin wax is provided as an aqueous emulsion, the amount ofwater initially introduced takes into account the amount of waterpresent in the aqueous paraffin wax emulsion.

If necessary, an emulsifying agent (surfactant) is introduced into theinitial volume of water, for example Montanox 85 (registered trademark),sold by Seppic.

The water initially introduced is subjected, whether or not it comprisesa dispersing agent, to powerful stirring by an Ultra-Turrax stirrerrotating at 20,000 revolutions/minute.

The oil of type (b) is introduced into the aqueous volume under thispowerful stirring with the formation of a mixture maintained underpowerful stirring for five minutes, in order to form the “oil-in-water”emulsion.

At the end of these five minutes of vigorous stirring, said stirring isreduced, the rotational speed of the Ultra-Turrax being brought to 5000revolutions/minute. The aqueous paraffin wax emulsion is introduced intothe oil-in-water emulsion under this gentle stirring.

When the introduction of the aqueous paraffin wax emulsion is complete,the mixture of emulsions formed is subjected, for at most 90 minutes, togentle stirring, the rotational speed of the Ultra-Turrax beingmaintained at 5000 revolutions/minute.

At the end of this final stirring time, the composition is ready to bemade use of by spraying, at the rate of 100 g/m², a compositioncomprising a solids content of 50% by weight.

Ten formulations with compositions Ai (with i=1 to 10) were prepared,the percentages by weight of the components of which are given in tableI below.

TABLE I % by weight of the % by weight total of % by weight of % byweight the water of paraffin paraffinic of total Formulation in the waxsolids oil of type solids No. emulsion content (b) content A 1 37.0063.00 (1) 0 63.00 A 2 55.00 45.00 (2) 0 45.00 A 3 50.00 30.00 (2) 20.0050.00 A 4 50.00 25.00 (2) 25.00 50.00 A 5 50.00 20.00 (2) 30.00 50.00 A6 50.00 15.00 (2) 35.00 50.00 A 7 50.00 10.00 (2) 40.00 50.00 A 8 50.0050.00 (3) 0 50.00 A 9 50.00 35.00 (3) 15.00 50.00 A 10 50.00 30.00 (3)20.00 50.00 (1) Redesmol 300 paraffin wax (2) Mobilcer 115 paraffin wax(3) Mobilcer 730 paraffin wax

In addition, each of these ten formulations comprised 1% by weight of anemulsifying agent (surfactant) which is Montanox 85.

In the abovementioned table I, the percentage by weight of water presentin the composition according to the invention is the total of waterpresent in the aqueous paraffin wax emulsion employed and of the waterintroduced as extra, the percentage by weight of paraffin wax being thusexpressed as percentage by weight of solids content, as well as thepercentage by weight of the paraffinic oil of type (b).

By way of comparison, the formulations A1, A2 and A8 of aqueous emulsioncompositions were prepared, each comprising one type of paraffin waxemployed alone or employed in the seven other formulations, in order tomake possible experimental comparisons.

The formulations of each of these comparative compositions are given intable II below.

Tests on the use of said compositions were carried out in the form of asprayed layer for each of them, deposited on the surface of freshlyplaced or freshly demolded concrete slabs, applied in order to provideboth water retention within said concretes during the setting and thentheir hardening and adhesion of the ceramic tiles to said surfaces ofthe treated slabs (constituting the test slabs) and of the untreatedslabs (constituting the control slabs).

These tests on protecting surfaces and on improving adhesivenesses werecarried out at an equivalent dosage, this dosage being 100 g/m² of eachemulsion A1 to A10.

The results of the improved adhesiveness and water retention have beencombined in table II below in the form of a coefficient of protection at6 hours and 24 hours after the pouring of the concrete, which indicatesthe percentage by weight of water maintained on the treated surfaces,and of a tension value in MPa, given by a tensile testing device at themoment when each ceramic tile is torn off.

TABLE II Measurement of the adhesiveness at the treated and untreatedCoefficient of surfaces protection for the Tension value in MpaFormulation treated surfaces Treated Untreated No. at 6 hours at 24hours surface surface (Control) 91.7 86.9 0.93 1.33 A1 (Control) 26.017.1 0.76 1.33 A2 A3 99.3 96.7 0.36 1.5 A4 100 96.5 0.24 1.5 A5 95.693.0 0.16 1.5 A6 93.6 91.5 0.46 1.5 A7 90.5 88.6 0.32 1.5 (Control) 18.014.7 0 1.68 A8 A9 95.7 91.2 0 1.68 A10 90.1 87.6 0 1.68

The comments which may be drawn from these two tables are as follows:

-   -   there is clearly synergy as regards retention of water in the        compositions as the comparison of the formulations A3 to A7 or        A9 to A10, comprising the paraffin wax and the oil, and the        formulations A1, A2 and A8, for the paraffin wax alone, shows        that the simultaneous presence of the oil and of the paraffin        wax in the aqueous emulsion composition leads to results as        regards water retention which are much better than the results        of the controls;    -   a phenomenon of maximization of the protection of the treated        surfaces occurs when the ratio of the percentages by weight of        oil to the percentages by weight of paraffin wax solids content        in the compositions is very preferably between 0.64 and 9;    -   protection of the treated surfaces is achieved with a low amount        of dry active material of the compositions with respect to the        control compositions;    -   the adhesivenesses of the formulations A3 to A7 comprising        paraffin wax and oil are not very satisfactory;    -   the formulations comprising the paraffin wax Mobilcer 730 are        ineffective with regard to adhesiveness.

EXAMPLE 2

This example relates to curing compositions comprising latexes butdevoid of inorganic fillers.

Compositions according to the invention were prepared in the form of anaqueous emulsion, which compositions are formed of:

-   -   paraffin wax: Mobilcer 115 (registered trademark), sold by Mobil        in the form of an aqueous emulsion with a solids content of 45%        by weight;    -   oil of type (b), which is a paraffinic oil with a low viscosity        equal to 20 mm²/s, sold by Mobil under the trade name 60        Neutral;    -   latex: Primal AC261 K, sold by Rohm & Haas;        -   LS2, sold by Goodyear;        -   Mowiton M 360, sold by Hoechst;        -   Orgal PST 50, sold by Organik Kimya;        -   Plextol D498 or B500, sold by Carrechim;        -   Vinamul 3249, sold by Vinamul;        -   Dowlatex 465, sold by Lambert-Rivière,            which are acrylic, stryrene/acrylic, acrylic/methacrylate,            vinyl acetate/ethylene or styrene/butadiene polymers or            copolymers;    -   water: q.s. for 100% by weight.

The method of preparation of the compositions is the same as thatdescribed in example 1, it being understood, however, that, after thecompletion of the introduction of the aqueous paraffin wax emulsion, thelatex emulsion is introduced in its turn with gentle stirring. Themixture of emulsions formed is then subjected, for at most 90 minutes,to the same gentle stirring, the rotational speed of the Turax beingmaintained at 5000 revolutions/minute.

Fifteen formulations were prepared, the percentages by weight of thecomponents of which are given in table III. These formulations Bj (j=1to 15) result from certain formulations Ai (i=1 to 10) resulting fromexample 1, to which at least one latex has been added.

TABLE III % by weight of solids Total % by content of weight of % byweight % by weight the water in of latex of total Formulationformulation the solids solids Bj No. Ai employed emulsion contentcontent B1 30 of A4 50.00 20 Vinamul 50.00 3171 B2 30 of A4 50.00 20Dowlatex 50.00 B3 20 of A4 50.00 30 Dowlatex 50.00 B4 10 of A4 50.00 40Dowlatex 50.00 B5 30 of A4 50.00 20 Primal 50.00 AC 261 K B6 30 of A450.00 20 Orgal 50.00 PST 50 B7 30 of A4 50.00 20 LS2 50.00 B8 30 of A450.00 20 MM 360 50.00 B9 30 of A4 50.00 20 PD498 50.00 B10 25 of A450.00 25 MM 360 50.00 B11 20 of A4 50.00 30 PD498 50.00 B12 30 of A550.00 20 PD498 50.00 B13 30 of A3 50.00 20 PD498 50.00 B14 20 of A450.00 30 MM 360 50.00 B15 25 of A4 50.00 25 PD498 50.00

Each formulation Bj is obtained by taking a percentage of a formulationAi resulting from table I made up by the introduction of a latex.

Tests on the use of said compositions were carried out in the form of asprayed layer for each of them, deposited on the surface of freshlyplaced or freshly demolded mortars and/or concretes, applied to provideimproved adhesiveness and water retention of said surface mortars orconcretes during the setting and then their hardening

These tests were carried out at an equivalent dosage, this dosage being150 g/m² of the emulsion with a solids content of 50%.

The results of this water retention and of the improved adhesivenesshave been combined in table IV in the form of a coefficient ofprotection at 6 hours and 24 hours after the pouring of the concrete,which indicates the percentage by weight of water maintained on thetreated surfaces, and a tension value in MPa for the measurement of theimproved adhesiveness at the surfaces treated by said compositions andat the untreated surfaces constituting the controls.

TABLE IV Measurement of adhesiveness Water retention of the at thetreated and treated surfaces untreated surfaces Coefficient of Tensionvalue in MPa Formulation protection Treated Untreated Bj No. at 6 hoursat 24 hours surface surface B1 99.6 95.8 0.71 1.51 B2 99.7 95.9 0.821.51 B3 98.2 94.7 1.21 1.51 B4 96.6 92.8 1.50 1.51 B5 99.3 95.2 0.971.42 B6 99.7 95.5 1.10 1.42 B7 99.8 95.8 0.53 1.36 B8 99.4 94.9 0.271.36 B9 99.8 96.0 0.56 1.36 B10 98.3 94.7 0.47 1.36 B11 95.4 92.8 1.231.36 B12 95.7 93.1 0.43 1.36 B13 99.4 96.5 0.32 1.36 B14 98.6 95.0 0.551.36 B15 98.5 94.8 0.56 1.36

In the abovementioned table III:

-   -   the percentage by weight of water present in the composition is        the total of the water present in the Mobilcer 115 emulsion        (with a solids content of 45% by weight), the percentage by        weight of paraffin wax thus being expressed as percentage by        weight of solids content, and the paraffinic oil employed;    -   the compositions Bj have received 1% of an emulsifying agent        which is a nonionic agent, sorbitan ester, having 85 ethylene        oxide units, sold under the trade name Montanox 85 by Seppic.

The adhesivenesses of the compositions Bj (j=1 to 15) compared with theadhesivenesses of Ai from which the Bj formulations result, that is tosay, the adhesivenesses of:

-   -   B1 to B11, B14 and B15 are to be compared with that of A4 (table        II), which is 0.24,    -   B12 is to be compared with that of A5 (table II), which is 0.16,    -   B13 is to be compared with that of A3 (table II), which is 0.36.

These comparisons already show a significant increase in thisadhesiveness.

The comparisons of the adhesivenesses of the compositions B2, B3 and B4with one another, of the compositions B9, B11 and B15 with one anotherand of the compositions B8, B10 and B14 with one another also show thatthe increase in the latex content of said compositions results in anincrease in the adhesiveness of said compositions.

EXAMPLE 3

This example relates to curing and improved adhesion compositionscomprising latex and pulverulent inorganic filler.

Compositions Ck (k=1, 2 or 3) were prepared according to the invention,which compositions are formed of:

-   -   paraffin wax: Mobilcer 115 (registered trade name), sold by        Mobil in the form of an aqueous emulsion with a solids content        of 45% by weight;    -   oil of type (b), which is a paraffinic oil with a low viscosity        equal to 20 mm²/s, sold by Mobil under the registered trade name        60 Neutral;    -   latex: copolymer of acrylic and methacrylic acids which is        Plextol D498, sold by Carrechim;    -   pulverulent inorganic filler: calcium carbonate with a specific        surface of 20 m²/g, microsilica with a specific surface of 450        m²/g or silica fume with a specific surface of 27 m²/g;    -   emulsifying agent (surfactant): 1% by weight of Montanox 85,        sold by Seppic;    -   water: q.s. for 100% by weight.

The method of preparation of this composition is the same as thatdescribed in example 1, it being specified that, after the completion ofthe introduction of the aqueous paraffin wax emulsion:

-   -   the latex emulsion is introduced in its turn with gentle        stirring;    -   then the mixture is subjected to powerful stirring by the Turax        stirrer rotating at 20,000 revolutions/minute and, under this        powerful stirring, the inorganic filler is introduced into the        aqueous volume with the formation of a mixture, under this        powerful stirring, over five minutes;    -   when the introduction of the inorganic filler is complete, the        resulting mixture is subjected to gentle stirring via the Turax        stirrer, the speed of which is brought from 20,000        revolutions/minute to 5,000 revolutions/minute, which gentle        speed is maintained for 90 minutes.

At the end of this final stirring time, the composition according to theinvention is ready to be made use of by spraying, at the rate of 150g/m², a composition with a solids content of approximately 50% byweight.

Three formulations were prepared, the percentages by weight of thecomponents of which are given in this table V below.

TABLE V Composition C1 Composition C2 Composition C3 as % by weight as %by weight as % by weight of solids of solids of solids content contentcontent % by weight of 48.95 48.95 48.95 the total of the water in theemulsion % by weight of 1 1 1 emulsifying agent % by weight of 20 20 20latex solids content % by weight of 0.05 of CaCO₃ (1) 0.05 of 0.05 ofsilica inorganic pyrogenic fume (3) filler silica (microsilica) (2) (1)with a mean diameter of 40 μm and a BET specific surface of 20 m²/g (2)with a mean diameter of 50 μm and a BET specific surface of 450 m²/g (3)with a mean diameter of 40 μm and a BET specific surface of 27 m²/g

Tests on the use of said compositions were carried out in the form of asprayed layer for each of them, deposited on the surface of freshlyplaced or freshly demolded concrete slabs, applied to provide both waterretention within said concretes during the setting and then theirhardening and adhesion of the ceramic tiles to said surfaces of thetreated slabs (constituting the test slabs) and of the slabs treatedwith the same composition devoid of inorganic filler (constitutingcontrol slabs).

These tests on protecting surfaces and on improving adhesivenesses werecarried out at an equivalent dosage, this dosage being 150 g/m² of theemulsion.

The results of the improved adhesiveness and water retention have beencombined in table VI below in the form of a coefficient of protection at6 hours and 24 hours after the pouring of the concrete, which indicatesthe percentage by weight of water maintained on the treated surfaces,and of a tension value in MPa, given by a tensile testing device at themoment when each ceramic tile is torn off.

TABLE VI Measurement of the adhesiveness at the treated surfaces Tensionvalue in MPa Surface Surface treated treated with with Coefficient offiller- composition protection for the comprising Ck without Formulationtreated surfaces composition inorganic No. at 6 hours at 24 hours Ckfiller C1 99.4 95.0 0.67 0.53 C2 99.8 95.8 0.98 0.53 C3 99.0 94.7 0.620.53

Comparison of the adhesivenesses between the compositions C1, C2 and C3,comprising pulverulent inorganic fillers (CaCO₃, microsilica and silicafume), and the same compositions devoid of said pulverulent inorganicfillers (controls) shows that the inorganic filler in combination with alatex greatly increases the adhesiveness.

The silica-based inorganic filler results in a much greater adhesivenessthan that of the calcium carbonate, at equal % by weight, being 0.05%,whether this adhesiveness increases as the specific surface of theinorganic filler increases.

EXAMPLE 4

This example relates to curing and improved adhesion compositionscomprising various latexes and pulverulent inorganic fillers.

Compositions De (e=1 to 6) were prepared according to the invention,which compositions are formed of:

-   -   paraffin wax: Mobilcer 115 (registered trade name), sold by        Mobil in the form of an aqueous emulsion with a solids content        of 45% by weight;    -   oil of type (b), which is a paraffinic oil with a low viscosity        equal to 20 mm²/s, sold by Mobil under the registered trade name        60 Neutral;    -   latex: copolymer of acrylic and methacrylic acids which is        Plextol D498, sold by Carrechim;    -   pulverulent inorganic filler: calcium carbonate with a specific        surface of 20 m²/g or silica with a specific surface of 450        m²/g;    -   emulsifying agent (surfactant): 1% by weight of Montanox 85,        sold by Seppic;    -   water: q.s. for 100% by weight.

The method of preparation of this composition is the same as thatdescribed in example 3.

Formulations Dl (l=1 to 4) were prepared, the percentages by weight ofthe components of which are given in table VII below.

TABLE VII % by weight % by of total weight of % by solids FormulationTotal % latex weight of content of from which by weight solids inorganicthe Dl Dl results of water content filler composition D1 B13 50.00 200.07 50.00 (PD498) CaCO₃ (1) D2 B7 50.00 20 (LS2) 0.05 50.00 CaCO₃ (1)D3 B11 50.00 30 (PD498) 1.36 50.00 Silica (2) D4 B15 50.00 25 (PD498)1.21 50.00 Silica (2) * formulation Dl resulting from the formulation Bj(1) CaCO₃, with a specific surface of 20 m²/g (2) Sipermat 50, with aspecific surface of 450 m²/g

Tests on the use of said compositions were carried out in the form of asprayed layer for each of them, deposited on the surface of freshlyplaced or freshly demolded concrete slabs, applied to provide both waterretention within said concretes during the setting and then theirhardening and adhesion of the ceramic tiles to said surfaces of thetreated slabs (constituting the test slabs) and of the slabs treatedwith the same composition devoid of inorganic filler (constitutingcontrol slabs).

These tests on protecting surfaces and on improving adhesivenesses werecarried out at an equivalent dosage, this dosage being 150 g/m² of theemulsion.

The results of the improved adhesiveness and water retention have beencombined in table VIII below in the form of a coefficient of protectionat 6 hours and 24 hours after the pouring of the concrete, whichindicates the percentage by weight of water maintained on the treatedsurfaces, and of a tension value in MPa, given by a tensile testingdevice at the moment when each ceramic tile is torn off.

TABLE VIII Measurement of the adhesiveness at the treated and untreatedsurfaces Tension value in MPa Coefficient Surface Surface of protectiontreated treated for the with with treated filler- composition surfacescomprising Dl without Formulation at 6 at 24 composition inorganicUntreated Dl No. hours hours Dl filler surface D1 0.75 0.32 1.36 D2 0.670.53 1.36 D3 1.33 1.23 1.36 D4 0.67 0.56 1.36

The following observations are extracted from this table:

-   -   the simultaneous increase in latex and in pulverulent inorganic        filler results in excellent adhesiveness of the compositions        according to the invention, it being possible for this        adhesiveness to reach that of concrete surfaces untreated by        said compositions and this adhesiveness exceeding the        adhesiveness of the compositions of the same origin but devoid        of the pulverulent inorganic filler.

1. A composition intended to be applied to the surfaces of freshlyplaced or freshly demolded mortars and/or concretes, before thebeginning of setting, in order to prevent the evaporation of the waternecessary for their setting and for their hardening and to create, onsaid surfaces, high adhesiveness of the finishing materials, whichcomposition is provided in the form of an aqueous emulsion comprising:a) from 5% to 60% by weight of at least one paraffin wax of petroleum orsynthetic origin including, as a mixture, saturated and unsaturatedaliphatic hydrocarbons of general formulae C_(n)H_(2n+2) and C_(n)H_(2n)for which n is at least equal to 30 and for which the melting point isbetween 40° C. and 75° C.; b) from 8% to 40% by weight of at least onehydrocarbon compound which is a linear or cyclic hydrocarbon oil ofaliphatic or naphthenic origin, alone or as a mixture, of generalformulae C_(n)H_(2n+2) and C_(n)H_(2n) for which n is less than 30; c)from 10% to 50% by weight of at least one ester-containing oil formed ofat least one ester resulting from the condensation reaction of asaturated or unsaturated fatty acid with a mono-, di- or trihydricalcohol; d) from 15% to 35% by weight of solids content of at least onelatex formed of a colloidal aqueous emulsion of at least one polymer; e)from 0.02% to 5% by weight of at least one pulverulent filler ofinorganic or organic origin; f) and of water in a quantity sufficientfor 100%.
 2. The composition as claimed in claim 1, wherein the ratio byweight, as dry active material, of the total of the oils and paraffinwax present is at least equal to 0.25.
 3. The composition as claimed inclaim 2, wherein said composition has a dry matter content of between10% to 60% by weight.
 4. A process for the preparation of thecomposition as defined in claim 3, characterized in that the processcomprises successive introduction of the various components of thecomposition into a preparation region subjected to stirring, thecontents of which can be heated or cooled, comprising the steps of: i)introducing into said preparation region a pre-determined amount ofwater and adding an emulsifying agent; ii) stirring the water andemulsifying agent to produce a homogeneous medium; iii) adding a mixtureof the at least one hydrocarbon compound which is a linear or cyclichydrocarbon oil of aliphatic or naphthenic origin and the at least oneester-containing oil formed of at least one ester resulting from thecondensation reaction of a saturated or unsaturated fatty acid andstirring for a sufficient time to produce a first emulsion; iv) adding apre-determined amount of the paraffin wax into the first emulsion whilestirring: wherein the paraffin wax heated beforehand to a temperaturesufficient to cause the paraffin wax to melt and to convert the paraffinwax into the emulsion state, when the paraffin wax is introduced in theform of a very fine powder; or wherein the paraffin wax is at ambienttemperature, when the paraffin wax is introduced in the form of anaqueous emulsion; and stirring for a sufficient time to form a secondemulsion, with optional cooling of the second emulsion; v) adding to thesecond emulsion a pre-determined amount of the at least one latex, andstirring for a sufficient time to produce a third emulsion of theparaffin, the hydrocarbons and the latex components; and vi) adding tothe third emulsion a predetermined amount of the at least onepulverulent filler of inorganic or organic origin and stirring for asufficient time to form a homogenous aqueous emulsion.
 5. A method ofprotecting against evaporation of water and increasing the adhesion ofthe surfaces of freshly placed or freshly demolded mortars and/orconcretes comprising the step of spraying composition as defined inclaim 3, as an aqueous emulsion, over said surfaces in a proportion of aworking load deposited per unit of surface area of between 50 g/m² and150 g/m² in order to achieve complete protection.
 6. The composition ofclaim 1, wherein the composition comprises: a) from 5% to 40% by weightof at least one paraffin wax of petroleum or synthetic origin; b) from9% to 30% by weight of at least one hydrocarbon compound which is alinear or cyclic hydrocarbon oil of aliphatic or naphthenic origin; c)from 15% to 40% by weight of at least one ester-containing oil formed ofat least one ester resulting from the condensation reaction of a fattyacid and an alcohol; d) from 15% to 35% by weight of solids content ofat least one latex formed of a colloidal aqueous emulsion of at leastone polymer; e) from 0.02% to 5% by weight of at least one pulverulentfiller of inorganic or organic origin; f) and of water in a quantitysufficient for 100%.
 7. The composition of claim 2, wherein the ratio byweight, as dry active material, of the total of the oils and paraffinwax present is at least equal to 0.63.
 8. The composition of claim 7,wherein the ratio by weight, as dry active material, of the total of theoils and paraffin wax present is between 0.64 and
 9. 9. The compositionof claim 3, wherein said composition has a dry matter content of between30% by weight and 50% by weight.
 10. A composition intended forapplication to the surfaces of freshly placed or freshly demoldedmortars or concretes, before the beginning of setting, in order toprevent the evaporation of the water necessary for their setting and fortheir hardening and to create, on said surfaces, high adhesiveness ofthe finishing materials, which composition is provided in the form of anaqueous emulsion comprising at least one paraffin wax alone or incombination with at least one other hydrocarbon compound, comprising: a)at least one paraffin wax of petroleum or synthetic origin including, asa mixture, saturated and unsaturated aliphatic hydrocarbons of generalformulae C_(n)H_(2n+2) and C_(n)H_(2n) for which n is at least equal to30 and for which the melting point is between 40° C. and 75° C., whereinthe at least one paraffin wax is present in said composition in aproportion of 5% to 60% by weight; b) at least one hydrocarbon compoundwhich is a linear or cyclic hydrocarbon oil of aliphatic or naphthenicorigin, alone or as a mixture, of general formulae C_(n)H_(2n+2) andC_(n)H_(2n) for which n is less than 30, present in said composition ina proportion of 8% to 40% by weight; c) at least one ester-containingoil formed of at least one ester resulting from the condensationreaction of a saturated or unsaturated fatty acid with an alcohol havingfrom one to five hydric functional groups, present in said compositionin a proportion of 10% to 50% by weight; d) at least one latex formed ofa colloidal aqueous emulsion of at least one polymer or copolymer as anemulsion in water, the at least one polymer or copolymer selected fromthe group consisting of homopolymers of acrylic acid, of methacrylicacid and of the esters of these acids, the ester group of which is a C₁to C₁₂ alkyl group, copolymers of acrylic acid, of methacrylic acid orof the esters of these acids, the ester group of which is a C₁ to C₁₂alkyl group, copolymers of vinyl and of acrylic acid or of methacrylicacid, copolymers of vinyl and of C₁ to C₁₂ esters, copolymers of acrylicor methacrylic acid, copolymers of acrylic acid or of methacrylic acidand of acrylic or methacrylic esters, styrene/acrylic or methacryliccopolymers, copolymers of ethylene and of vinyl acetate, copolymers ofethylene and of acrylic or methacrylic acid, acrylic/urethane copolymersand styrene/butadiene copolymers, present in said composition in aproportion of 15% to 35% by weight of solids content; e) at least onepulverulent filler of inorganic or organic origin present in saidcomposition in a proportion of 0.02% by weight to 5% by weight; f) andwater in a quantity sufficient for 100% by weight.
 11. The compositionof claim 10, wherein: a) the at least one paraffin wax is present insaid composition in a proportion of 5% to 40% by weight; b) the at leastone hydrocarbon compound which is a linear or cyclic hydrocarbon oil ofaliphatic or naphthenic origin is present in said composition in aproportion of 9% to 30% by weight; c) the at least one ester-containingoil formed of at least one ester resulting from the condensationreaction of a fatty acid and an alcohol is present in said compositionsin a proportion of 15% to 40% by weight; d) the at least one latexformed of a colloidal aqueous emulsion of at least one polymer orcopolymer as an emulsion in water is present in said compositions in aproportion of 15% to 35% by weight of solids content; e) the at leastone pulverulent filler of inorganic or organic origin is present in saidcompositions in a proportion of 0.02% by weight to 5% by weight; andwater is present: in a quantity sufficient for 100% by weight.